A triangle has sides A,B, and C. If the angle between sides A and B is π3, the angle between sides B and C is π6, and the length of B is 9, what is the area of the triangle?

1 Answer
Dec 28, 2015

17.537

Explanation:

As the sum of all the angles of a triangle is 1800 or π radians
So, from your sum it can be seen that the third angle between A and C =ππ3π6=π2
Thus making the side B, which is opposite to the 900 angle hypotenuse of the triangle.
So, the area of the triangle would be 12baseheight=12AC
Given that side B=9, we can find the other two side by triangle geometry
A=Bcos(π3)=9cos(π3)=4.5
C=Bsin(π6)=9sin(π6)=7.794
Hence, Area=12AC=124.57.794=17.537